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What if my Windows Mobile device + does not support SetFilePointer and/or + SetEndOfFile?
+ You can manually disable the truncate functionality + from the build. +
+ Do that by opening the + db-X.X.X/build_wince/db_config.h + file, and change the line that reads +
```
#define HAVE_FTRUCATE 1
```
+ to read +
```
#undef HAVE_FTRUNCATE
```
+ Making this change disables DB->compact() for btree + databases. +
- What if my Windows Mobile device does not support SetFilePointer and/or SetEndOfFile? + Why doesn't automatic log archiving work? -
You can manually disable the truncate functionality from the build.
-
Do that by opening the db-X.X.X/build_wince/db_config.h file, and change the line that reads
-
```
#define HAVE_FTRUCATE 1
```
-
to read
-
```
#undef HAVE_FTRUNCATE
```
-
Making this change disables DB->compact() for btree databases.
+
+ The Windows Mobile platform does not have a concept + of a working directory. This means that the + DB_ARCH_REMOVE and DB_ARCH_ABS flags do not work + properly within Windows Mobile, because they rely on + having a working directory. +
+
+ To work around this issue, you can call log_archive + with the DB_ARCH_LOG flag, the list of returned file + handles will not contain absolute paths. Your + application can take this list of files, construct + absolute paths, and delete the files. +
- Why doesn't automatic log archiving work? + Does Berkeley DB support Windows Mobile? -
The Windows Mobile platform does not have a concept of a working directory. This means that the DB_ARCH_REMOVE and DB_ARCH_ABS flags do not work properly within Windows Mobile, because they rely on having a working directory.
-
To work around this issue, you can call log_archive with the DB_ARCH_LOG flag, the list of returned file handles will not contain absolute paths. Your application can take this list of files, construct absolute paths, and delete the files.
+
+ Yes. +
+
+ Berkeley DB relies on a subset of the Windows API, + and some standard C library APIs. These are provided + by Windows CE. Windows Mobile is built "on top" of + Windows CE. +
- Does Berkeley DB support Windows Mobile? + Does Berkeley DB support Windows CE?
Yes.
-
Berkeley DB relies on a subset of the Windows API, and some standard C library APIs. These are provided by Windows CE. Windows Mobile is built "on top" of Windows CE.
+
+ Berkeley DB relies on a subset of the Windows API, + and some standard C library APIs. These are provided + by Windows CE. +
- Does Berkeley DB support Windows CE? + Does Berkeley DB support Windows Embedded + Compact 7?
Yes.
-
Berkeley DB relies on a subset of the Windows API, and some standard C library APIs. These are provided by Windows CE.
+
+ Starting from release 12.1.6.1, it is possible to build Berkeley DB + on Windows Embedded Compact 7. Below are tips for the build process: +
+
+
1. + + Compile error at line 146 in stdlib.h + +
  + This is a known bug for the Windows Embedded Compact 7 SDK. + A workaround is to change the line 146 in stdlib.h to read: +
  +
```
__checkReturn __bcount(_Size) void * __cdecl _alloca(__in size_t 
+_Size);
```
  +
2. + + error LNK2019: unresolved external symbol _localtime_s referenced in function _osLocaltime + +
  + This link error is caused by the fact that the Windows + Embedded Compact 7 runtime used to link Berkeley DB does not + provide the localtime_s() function. A workaround is to add +
  +
```
HAVE_LOCALTIME_S=0
```
  +
  + to the proprocessor definitions of the db_sql project. This + can be done by right clicking the db_sql project, select + Properties->Configuration Properties->C/C++->Preprocessor->Proprocessor Definitions, + and append
  +
```
HAVE_LOCALTIME_S=0
```
  +
  + at the end of the list. +
  +
3. + + error LNK1221: a subsystem can't be inferred and must be defined + +
  + This link error happens on Visual Studio 2008, because it + cannot understand the subsystem configured for Visual + Studio 2005. To fix this error, right click the project + reporting this link error, select Properties->Configuration Properties-> + Linker->System->SubSystem, and change the value to WindowsCE (/SUBSYSTEM:WINDOWSCE). +
  +
4. + + warning C4996: 'xxx': This function or variable may be unsafe. + +
  + Used within the Berkeley DB source tree, these functions are actually safe. + You can safely ignore these warnings. +
  +
+
- What platforms are the supplied sample applications designed for? + What platforms are the supplied + sample applications designed for? -
The supplied sample applications were developed for the Pocket PC 2003 emulator. They are known to work on real pocket PC devices and later versions of the emulator as well.
-
The supplied applications are not designed to work with Smartphone devices. The screen size and input mechanisms are not compatible.
+
+ The supplied sample applications were developed for + the Pocket PC 2003 emulator. They are known to work on + real pocket PC devices and later versions of the + emulator as well. +
+
+ The supplied applications are not designed to work + with Smartphone devices. The screen size and input + mechanisms are not compatible. +
- I see a file mapping error when opening a Berkeley DB environment or database. What is wrong? + I see a file mapping error when + opening a Berkeley DB environment or database. What is + wrong? -
The default behavior of Berkeley DB is to use memory mapped files in the environment. Windows Mobile does not allow memory mapped files to be created on flash storage.
-
There are two workarounds:
+
+ The default behavior of Berkeley DB is to use memory + mapped files in the environment. Windows Mobile does + not allow memory mapped files to be created on flash + storage. +
+
+ There are two workarounds: +
1. - Configure the Berkeley DB environment not to use memory mapped files. The options are discussed in detail in - Shared memory region. -
2. Create the Berkeley DB environment on non-flash storage. It is possible to store database and log files in a different location to using the DB_ENV->set_data_dir() and DB_ENV->set_lg_dir() APIs.
3. + Create the Berkeley DB environment on + non-flash storage. It is possible to store + database and log files in a different location to + using the DB_ENV->add_data_dir() and DB_ENV->set_lg_dir() + APIs. +

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